DESCRIPTION (APPLICATION ABSTRACT): This project will examine the relationships that exist between and among key features of the organizational workplace, the workforce, and adverse patient events due to preventable errors in the home health care setting. Taking advantage of the natural variation in working conditions across 83 teams in a very large home health agency, the project will estimate the effects of variations in team culture and staffing, as well as individual nurse characteristics and productivity, on adverse patient events. It also will examine the relationship between patient care errors and selected adverse events. Measures of work environment and workforce characteristics will include both objective and subjective measures and will be obtained from a combination of routine administrative and clinical data, plus project-specific primary data, including a survey of frontline nurses and managers. Measures of adverse patient events will be drawn from a set of 13 measures developed by the Health Care Financing Administration for home health care, supplemented by a small number of additional measures selected with input from an expert panel. The project will employ qualitative methods (interviews, expert panel, focus groups) to elaborate the conceptual model and hypotheses, as well as to review and interpret the findings of the quantitative analyses. It will employ econometric techniques, including the use of instrumental variables, to model episode and patient level outcome data (adverse events) at the team and nurse level. It also will involve record review and statistical analysis to assess the strength of the relationship between patient care errors and three types of adverse events. The project will be one of the few theory-driven empirical, quantitative studies of home health care quality. It should lead to sounder intervention research and contribute to the broader literature on working conditions, service quality, and patient safety.